Wireless communications devices, such as cellular telephones (cell phones), commonly employ speech recognition tools to simplify the user interface. For example, many cell phones can recognize and execute user commands to initiate an outgoing phone call, or answer an incoming phone call. Many cell phones can recognize a spoken name from a phone book, and automatically initiate a phone call to the number associated with the spoken name.
Handheld electronic devices (e.g., mobile phones, PDAs, etc., referred to herein as “handhelds”) typically provide for user input via a keypad or similar interface, through which the user manually enters commands and/or alphanumeric data. Manually entering information may require the user to divert his attention from other important activities such as driving. One solution to this problem is to equip the handheld with an embedded speech recognizer.
Due to numerous factors, the speech recognizer may occasionally incorrectly decode the utterance from the user. To deal with such errors, some speech recognizers generate a list of N alternatives for the recognized transcript (i.e., the word or words corresponding to what the user uttered), referred to herein as the choice list (also known in the art as an N-best list), from which the user may choose the correct version. One factor contributing to incorrect recognitions that is particularly relevant in the following description is variations in user pronunciation. A user with a certain dialect or accent may utter a word that does not score well with the phonetic representation of that word stored in the lexicon of the speech recognizer.